This invention relates to a method of preventing car thefts and more particularly to an improved method and apparatus for locking a motor vehicle.
Many motor vehicles now employ locking systems that include a key which is not only keyed to a tumbler but which also carries a built-in transponder which works with a receiver mounted on the vehicle and normally as a part of the locking mechanism so as to contain a specific ID code. When the key is inserted into the locked cylinder, the transponder transmits a signal to the device and its ID is checked. If the proper ID is not registered, then it is impossible for the user to start the engine even if the key can be turned in the lock cylinder and thus, thefts are prevented.
Although this system has obvious advantages, there are some disadvantages to it. That is, there are times when due to either replacement of the key or replacement of the lock or vehicle mounted portion; it is necessary to reset the lock so as to use a key with a new ID. The method that has been done previously is quite cumbersome and involves either installing a new key cylinder that matches the previously key utilized or replacement of the transponder on the key with a proper one for the new lock. Both methods are cumbersome and also result in poor appearance for the key if the key is attempted to be repaired with a new transponder.
Also, there are times when the wrong ID code may be initially registered in the locking device. When this occurs, a special mechanism is required in order to erase all of the registered ID codes and then new codes must be programmed in. This has been a cumbersome and costly procedure.
It is, therefore, a principal object to this invention to provide an improved and simplified method and apparatus for registering a new ID in a lock of the locking mechanism of the type described.
It is a further object of this invention to provide an improved and simplified method and apparatus by which a lock of this type can have its memory erased and new ID numbers programmed into it.
It should be apparent that the mere ability to erase the IDs"" and program new IDs"" in place, presents a possibility of reduced protection from theft. However, in accordance with a further feature of the invention, the mechanism and method is designed so that only a specific pre-identified ID key can be utilized to erase the ID indications from the memory and place new IDs in it.
It is a further object to the invention to provide an improved method for operating a lock of this type and a lock that permits re-registration of IDs by authorized persons to provide theft protection and simplify correction of changing in either the key, the lock or correction of mistaken entries.
This invention is adapted to be embodied in a method of preventing vehicle thefts and key locking system for a vehicle that comprises a key cylinder and controller that are mounted on the vehicle and a key which is insertable into the key cylinder for switching on a main switch for activating a prime mover of the vehicle. The key has a built-in transponder containing an ID code of the key to be sensed when the key is inserted into the key cylinder by the controller.
In accordance with a method for performing the invention, the method comprises the steps of permitting the operation of the prime mover only when the ID code detected by the transponder coincides with an ID code, which has been registered in the controller. The controller is conditioned to memorize an ID code of a newly recognized key by inserting a key having a specific ID code into the key cylinder to turn the main switch on and withdrawing the key having the specific ID code without starting the prime mover. Thereafter, the ID code of the newly recognized key is memorized if inserted into the key cylinder within a predetermined time after the key having the specific ID code has been withdrawn.
In accordance with a key locking system of the type described, the controller is conditioned so as to recognize and memorize the ID code of a newly registered key if inserted into the key cylinder at a predetermined time after a previously registered key has been inserted into the key cylinder, the main switch turned on and the registered key withdrawn.